1. Field of the Invention
This invention relates to toy blocks and, more particularly, to hollow blowmolded plastic blocks having interconnecting arrangements.
2. Description of the Prior Art
Toy blocks have long been fabricated from many different materials. Wood, ceramics, metals, and plastics have all been used. Various different interlocking or interconnecting arrangements have also been utilized to allow the blocks to be interconnected with each other and removed from each other. Such arrangements include tongues and grooves, notches of various types, pin arrangements, protrusions and protrusion accepting apertures having various configurations, and the like.
Toy blocks, in general, are designed for children to entertain, educate, and aid in the development of improved physical dexterity. Many of the above different interconnecting combinations are specifically designed to appeal to children having particular age and mental development levels. Difficult interconnecting combinations generally appeal to older and more educationally developed children. However, simpler interconnecting arrangements are required for younger children, since, in the case of younger children, it is very important to provide toys which challenge the child but do not frustrate the child to the point that the child rejects the toys. The small fingers, lack of physical strength, and limited manual dexterity of younger children impose constraints on the design and fabrication of interconnecting toy blocks. Such toy blocks for such younger children must, therefore, be comparatively easy to connect together and disconnect. Such ease of interconnection and removal enhances the play value of the blocks. Further, it is also required that such blocks, when interconnected, are able to withstand the rigors and stresses normally associated with the use of the blocks without inadvertent disconnection.
Additionally, the blocks should also be able to provide a level of complexity and sophistication sufficient to maintain the interest of older children, or even adults, in order to extend the play life and utility thereof. These conflicting requirements have not, heretofore, been achieved in interconnecting toy block arrangements.
The development of plastics has allowed the molding of toy blocks in many new and more complex shapes. Plastics have also lowered the costs of production of the blocks. The lowest cost method of manufacturing of suitable plastic items is blowmolding. Blowmolding is a technique wherein a tube of hot plastic is extruded, inserted in a mold, and inflated with a gas forcing the walls of the tube to conform to the contours of the mold. One advantage of blowmolded plastics is that softer plastics may be utilized than can be utilized in injection molding techniques, thus allowing the product, for example, to be much softer than a comparable injection molded product. Another advantage of blowmolded products is that they tend to deflect easily upon being subjected to force and, at the same time, they tend to return to their original shape. However, attempts at using blowmolded plastics for children's toy blocks have not proven to be satisfactory because of the relatively close tolerances required to allow the toy blocks to interlock with each other satisfactorily. In addition, the blowmolded plastic blocks tend to be too soft to avoid being deflected beyond the point from which they can regain their original shapes and/or inadvertently disconnected when subjected to the substantial forces which children impose on their toys during the normal play time activities therewith.
Thus, the above, often conflicting, desiderata have not heretofore been achieved and, in particular, have not been achieved in blowmolded interconnecting toy block arrangements.